Rodney Buckmire MAT102 – Module 2 – Case Professor Choi Part 1 1. To get the standard deviation of these numbers I first calculated the mean by added all the numbers together (298, 125, 411, 157, 231, 213, 304, 272) and divided it by 8. I then took the mean(251.375) and calculated the deviance by subtracting the mean from each one of the numbers in the set. Then I squared each of the individual deviations, added those sums together, and divided the number I got from that sum by one less than the data set, which is 7 (8230.55357). Then the last step is calculating the square root, which is the ending result (90.7224) So the standard deviation of this set of numbers is 90.7224. 2. Set 1: Range : maximum - minimum = 154-110= 44 Number of cases 8 To find the mean, add all of the observations and divide by 8 Mean 125 Squared deviations (120-125)^2 = (-5)^2 = 25 (123-125)^2 = (-2)^2 = 4 (153-125)^2 = (28)^2 = 784 (128-125)^2 = (3)^2 = 9 (124-125)^2= (-1)^2= 1 (118-125)^2 = (-7)^2 = 49 (154-125)^2 = (29)^2 = 841 (110-125)^2 = (-15)^2 = 225 Add the squared deviations and divide by 8 Variance = 1938/7 Variance = 276.857 Standard deviation = sqrt(variance) = 16.639 Set 2: Range : 156-110 =46 Number of cases 8 To find the mean, add all of the observations and divide by 8 Mean 131.75

This preview
has intentionally blurred sections.
Sign up to view the full version.